Hydroponics is the soilless growing of plants. Hydroponics is an especially useful technique for producing food for livestock. The advantages of the use of hydroponics to produce livestock are that fresh food is available all year, the food that is available is free from undesirable materials such as weeds, wild garlic and onion plants, insects, dust, insecticides, radioactive fallout, to name a few. The product is also free of soil so the animals can eat the entire plant, root and all.
Properly designed hydroponic devices can yeild can enormous output of plant material in a short time. The yield is large and quick because of the opportunity to control germination, temperature, light, and food for the plants. It is not unusual to produce a nine-inch growth of grass from barley seed in 7 days, and the growth of grass produces a seven-fold increase in weight over the weight of the seeds that were employed.
Additionally, hydrophonic devices generally are less expensive to operate than growing the same amount of plant material in an open field. They are less expensive from the capital investment point of view because it is not necessary to own large amounts of land; and it is also less expensive from an operational point of view because extremely high yeilds can be obtained without much labor and without much machinery which is necessary to till and fertilize soil. Additionally, harvesting the products from a hydrophonic device is very easy. However, hydroponic growth of plant materials still involves many problems.
Among the problems are that the ideal growing conditions within the hydroponic device is very attractive to undesirable plant species such as fungus; energy consumption is high to provide adequate light for photosynthesis; and growing plants generate heat which must be removed if the temperature is to be maintained properly.